Seto nearly took the job at Washington with Sarkisian, but ultimately decided to stay in L.A. for family and church reasons.

He then became Carroll’s defensive coordinator after Nick Holt agreed to leave USC to take the same job with Sarkisian. Seto has been a Trojan assistant since 1999, previously coaching the safeties, linebackers and secondary after playing for USC as a walk-on linebacker.

But new USC coach Lane Kiffin dismissed Seto last week as he’s bringing his father, Monte Kiffin, in as defensive coordinator.

Seto would be the seventh member of last year’s USC staff to join the Seahawks, though he’ll have a fairly minor role as a quality control assistant.

Quality control coaches are generally entry-level positions on NFL staffs, used to help break down film, help with scouting and assist the coordinators.

Carroll’s staff appears near completion as he’s now hired 17 assistants, including the seven from USC. Mora had 17 assistants on his staff last year.

Given that Seto has never coached in the NFL, it’s not surprising he didn’t earn a bigger position on the Seahawks’ staff.

Seattle’s defensive unit will be headed by coordinator Gus Bradley, who was retained from Jim Mora’s staff along with defensive line coach Dan Quinn. Jerry Gray, a long-time NFL veteran, was hired from Buffalo to coach the secondary.

Norton has never coached in the NFL, but the son of former heavyweight champ Ken Norton was a 13-year NFL veteran with Dallas and San Francisco and went to three Pro Bowls and three Super Bowls during his pro career.

He was USC’s linebackers coach the past six years and will handle those same duties in Seattle.